Lol, I know that feeling! Some muses really do think the whole creative process revolves around what they want to do (see icon)

I find it's easier just to scribble out the main event to keep the muses happy, then lay it aside until you're ready for it and insist that you get back to work on the next chapter. That way, you don't lose any good ideas and have a base to start from when you do start that part.
It's worked for me anyway *shrugs* just a thought.